The man behind the Beslan school siege said Tuesday a failed Russian special services sting had allowed his militants a free passage into the region to conduct the attack that killed 330 people almost a year ago, Reuters news agency reports.

Shamil Basayev, Russia’s most wanted man, issued the statement on separatist website www.kavkazcenter.com days before the anniversary of the bloodbath and at a time when authorities face criticism for failing to clarify what happened.

Basayev said a special services agent had been sent undercover to the rebels to persuade them to plan an attack in Vladikavkaz, capital of the North Ossetia region bordering Chechnya. But the agent confessed to the rebels, who were then able to plan an alternative. They were allowed to enter the region with ease, with security services believing they would be able to capture them as they headed for Vladikavkaz, Basayev said.

But the rebels went instead to Beslan. “From August 31, they opened a way in for us ... and we went along it to Beslan, ’mixing up’ the time and target of the attack,” said Basayev, who describes himself as a terrorist.

The Russian government could not be reached for comment.

On Sept. 1, traditionally the beginning of the school year, rebels took more than 1,000 parents and children hostage in a school gymnasium and held them there for two days. Most of the 330 people who died were killed in the chaotic operation by Russian forces to free the hostages. Half were children.

Relatives of the dead have accused authorities of failing to investigate the tragedy properly and are angry that officials have not been taken to task for the role they played.

A parliamentary commission has yet to publish the findings of an inquiry it has been conducting. Newspapers have reported that Kremlin officials, including President Vladimir Putin, are unhappy with its progress.

Basayev, who last week was appointed deputy leader of Chechnya’s separatists, said his fighters had plenty of information to share. “We have a lot to tell but we have been waiting for the Russians to finish their ’investigation’. They are dragging out this process because they have nothing to tell people,” he said.

“Today we are ready for an open international inquiry to the Beslan events. We have a living participant in the operation who is prepared to give evidence.”

It was not clear whether he was referring to Nurpashi Kulayev, the Chechen who went on trial in May for his alleged part in the mass hostage-taking. He is believed to be the only militant to survive the siege.